What do you get when you combine social networking, college students, and career building tools? A successful startup. Allan Sahagun, the 19-year-old Harvard University student and co-founder of Alumwire, knows firsthand since the 2006 launch of his site. Sahagun knows how to choose his partners – Alumwire is powered with the help of Careerbuilder.com, the Wall Street Journal’s College Journal website, and of course Sahagun's brother Aaron.